<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="/web1/js/vue.js"></script>
    <style>
        #app{
            width: 600px;
            margin: 40px auto;
            text-align: center;
        }
    </style>
</head>
<body>
    <div id="app">
        <h2>当前计数器的值为:{{num}}</h2>
        <counter v-on:counter-add="num++"></counter>
    </div>

    
</body>
<script>
    Vue.component('counter',{
       
            
        template:'<button@click="add">计数器</button>',
        methods:{
            add:function(){
                this.$emit('counter-add')

            }
        }
    })
    let vm=new Vue({
        el:'#app',
        data:{
            num:0
        },
        methods:{
            handleAdd:function(){
                this.num++
            }
        }
    })
</script>
</html>